I have recently invested in a CO2 injection system. I must say my planted aquarium has never looked better. My question is for other CO2 injection users. I have an indicator that shows the CO2 is in the proper range but my 5 pound tank only last about 3 days. I have checked for leakage and have not found any leaks, Everything is snugg and I use the proper washers connecting to the tank. I will not be able to afford $12.00 every few days for CO2. My bubble counter is somewhat inconsistent even with the metering device to set the bubbles. When it comes on with my lights I always have to re-adjust the bubbles and sometimes speeds up on it's own hours later. Anyway, I typically set it to about 2 bubbles per second, is that too much? Any suggestions would be appreciated my experienced CO2 injection users. The fermentaion CO2 systems never seemed to work with only a puff of CO2 every now and then. THANKS in advanced.